1. Field of Invention
This invention relates generally to a high-accuracy system and method to be used in the computation of a vehicle's weight and balance. More specifically, this invention relates to real-time, automatic and high-accurate systems and methods for measuring individual passengers and luggage weight to be used for calculating an aircraft's exact weight and balance and load plan.
2. Description of Related Art
It is well known that inaccurate aircraft weight and balance estimates may contribute to airplane crashes, especially crashes of smaller planes that carry, for example, from 10-19 passengers. Currently, weight and balance estimates are used to avoid overloading an airplane, i.e., making it too heavy to safely fly, and avoiding weight imbalances, which also make airplanes difficult or impossible to fly safely. The current Federal Aviation Administration (FAA) advisory, e.g., AC 120-27C, which is used by most airlines require the airlines to use estimated passenger and/or passenger baggage weights. The average passenger and/or passenger baggage weight estimates provide generally, that the average passenger weight, including carry-on luggage, is 180 lbs. in the summer and 185 lbs. in the winter. Check-in bags are presumed to weigh 25 lbs. for domestic flights and 30 lbs. for international flights. However, the estimates obviously do not provide an accurate means to calculate a passenger airplane's total passenger weight. The airlines may ask passengers to divulge their weight. However, because most people might be expected to underestimate their weight, this method is also considered to provide an inaccurate means to determine the total passenger/passenger baggage weight of the aircraft. Equally as important as total passenger/baggage weight is passenger and carry-on baggage weight distribution because it affects an aircraft's center of gravity. For example, placing too many bags in the rear compartments of a vehicle such as, for example, an aircraft, or seating heavy people at the rear of the aircraft may significantly change a small plane's center of gravity and thereby make it relatively difficult to fly safely. Additionally, it is important to know the fuel weight and actual location so as to accommodate the precise information when calculating the required weight and balance.
U.S. Pat. Nos. 4,225,926 and 4,446,524 disclose ascertaining the individual weight of total load including that of passengers and hand baggage. The load is weighed using a sensing device such as a group of load cells or a platform that is arranged at the entrance door inside of the aircraft for passengers and the entrance to the freight compartment for baggage. Although the device disclosed in U.S. Pat. Nos. 4,225,926 and 4,446,524 allow for weighing passenger and baggage weight, it does not allow for any additional flexibility, such as arranging the platform at or near the gate terminal and/or check-in counter.
U.S. Pat. No. 3,584,503 discloses determining an aircraft's gross weight and center of gravity by incorporating strain gage transducers mounted in the landing gear axles and in the nose restraint, an attitude sensor, a processor and an indicator-control unit. The transducer provide electrical signals which are proportional to the landing gear loads. The processor receives and sums these signals to provide appropriate outputs to the gross weight and center of gravity indicators. However, the device disclosed in U.S. Pat. No. 3,584,503 cannot individually calculate and locate the weight of each passengers and baggage on an airplane.
Other known weight and balance systems determine overall weight and position of center of gravity of an aircraft through potentiometric level gauges or by measuring the trim correction drag. These systems do not allow a real-time measurement of the total weight and balance. Furthermore, such systems do not allow an accurate measurement of the total weight and balance.
None of these systems provide for measuring the precise weight and balance of an aircraft in real-time for each passenger and their baggage.